Casting is a manufacturing process where melting metal pours into a mold cavity. After metal solidified, metal casting is ejected or break out from the mold. Since the raw material of casting comes from the metallurgy melting metal, so when we talk about metallurgy casting, we are talking about casting or metal casting.
Casting is diversified on workmanship available. However, the most common casting process is sand casting that has the longest history.
Sand casting is a casting process in which melting metal pours into a sand mold. Besides, there have other special casting processes that are capable to make castings that sand casting is unable to do.
Some typical special casting workmanship is:
- Die Casting. A process to make nonferrous casting under high pressure, and mold is a permanent tool steel. For example, such as airport armrest aluminum casting.
- Gravity Casting. Also referred to as permanent mold casting. Mold is reusable, and iron or tool steel is the most common mold material. An example such as the nozzle handle for reference.
- Investment Casting. The lost wax pattern is a copy of sand mold to make steel casting.
- Lost foam Casting. The evaporated plastic pattern is the copy of the sand mold
- Shell Molding. Mold is an expandable mold covered with resin plastic. As a result, the baked resin shapes out a shell mold.
In general, the casting process has two types according to mold material. Expendable mold (sand mold) and Permanent mold (metal mold).
Process Selection Guide
The first step of process selection relies on the design of the casting. Therefore, the design needs to consider the application requirements on material and physical function.
Once the design intent determined, the process will be selected based on available casting processes and materials. Each casting material has its limit on process selection, and so does it for the casting process.
In conclusion, metallurgy casting is diversified workmanship to make intricate objects, it is versatile and the underlying process of modern industry.